Adds letsencrypt cluster issuer

gitops-kaisers-info/templates/letsencrypt.yaml

+apiVersion: cert-manager.io/v1alpha2
+kind: ClusterIssuer
+metadata:
+  name: letsencrypt
+spec:
+  acme:
+    email: simon.kaiser@gmx.net # replace this
+    privateKeySecretRef:
+      name: issuer-account-key
+    server: https://acme-v02.api.letsencrypt.org/directory
+    http01: {}
+    solvers:
+      - http01:
+          ingress:
+            class: traefik
+        selector: {}